1. Field of the Invention
The present invention relates to portable digital communication apparatuses, such as cellular phones, PDAs (personal digital assistants), HHPs (hand held phones), and PCS (personal communication service) phones, and more particularly to portable digital communication apparatuses having housings capable of making sliding and swing movements with respect to each other.
2. Description of the Related Art
In general, a “portable communication apparatus” refers to an electronic apparatus which a user can carry with him/her to perform wireless communication with a desired partner. In consideration of portability, designs of such portable communication apparatuses have emphasized compactness, slimness, and lightness, as well as the availability of multimedia functions, and having a wider variety of services and functions. In particular, portable communication apparatuses being developed are expected to incorporate greater multi-functionality and multi-purpose utilization, and are expected to be more compact and lighter, while at the same time being suitable for various multimedia environments or Internet environments. Such portable communication apparatuses are now commonly used and are recognized as a nearly indispensable commodity which must always be carried.
Conventional portable communication apparatuses may be classified into various types according to their appearance, such as bar-type portable communication apparatuses, flip-type portable communication apparatuses, and folder-type portable communication apparatuses. The bar-type portable communication apparatus has a single housing shaped like a bar. The flip-type portable communication apparatus has a flip which is pivotably mounted to a bar-shaped housing by a hinge unit. The folder-type portable communication apparatus has a folder coupled to a single bar-shaped housing by a hinge unit in such a manner that the folder can be pivoted in order to be folded to or unfolded from the housing.
Further, portable communication apparatuses may be classified into neck wearable type communication apparatuses and wrist wearable type communication apparatuses according to the position at or the way in which a user puts on or carries the communication apparatus. The neck wearable type communication apparatus is one which a user wears around the neck using a string or lanyard, while the wrist wearable type communication apparatus is one which a user wears around the wrist.
Additionally, portable communication apparatuses may be classified into rotation-type communication apparatuses and sliding-type communication apparatuses according to ways of opening and closing the communication apparatuses. In the rotation-type portable communication apparatus, two housings are coupled to each other in such a manner that one housing rotates to be opened or closed relative to the other while the housings face each other. In the sliding-type portable communication apparatus, two housings are coupled to each other in a manner that one housing slides to be opened or closed relative to the other. These variously classified portable communication apparatuses can be easily understood by those skilled in the art.
Meanwhile, conventional portable communication apparatuses are now generally equipped with a function of transmitting data at a high speed in addition to the basic function of performing voice communication. In other words, according to an increase in demand by consumers, portable communication apparatuses now can provide services using a wireless communication technology capable of transmitting data at a high speed.
Recent portable communication apparatuses now may be equipped with a camera lens which enables each of the communication apparatuses to transmit an image signal. That is, current conventional portable communication apparatuses may have an imbedded or external camera lens or a photographing means which enables a user to make an image communication with a desired partner or to take a photograph of a desired subject.
However, conventional portable communication apparatuses, in particular sliding-type portable communication apparatuses are sometimes inconvenient to use with respect to their key operations when they are used in an e-mail transmission mode, in a chatting mode, or in a PDA mode. This is due to the relatively small number of key arrays which may make it difficult to perform complex data input operations.